The Microarray Shared Resource is directed by Jan Vijg, Ph.D., and will provide SACI investigators with up to 200 mouse or human microarrays annually, containing approximately 2,000 different genes, printed as cDNAs or synthetic DNAs in duplicate on glass slides. Custom-arrays will also be printed upon requests from San Antonio Cancer Institute (SACI) members. In addition, the Cancer Center investigators will be offered a full expression profiling service based on RNA extraction from the target tissue/cells, slide hybridization, slide scanning, and quantification. For arrays and services, part of the personnel and reagent costs will be recovered through charge-backs to the users. We have estimated that this will translate to a charge of $90 per slide and $450 for complete slide hybridization, scanning, and quantitation service. This is approximately four times less than its commercial equivalent and will allow the SACI members to conduct gene expression profiling studies at a sufficient level of replicate experiments to obtain statistically meaningful results. The Microarray Shared Resource is located on the third floor of the South Texas Centers for Biology in Medicine (STCBM) building in the Texas Research Park, next to the Institute of Biotechnology. The core occupies two laboratories: the first is a 600 square foot open laboratory that is used for DNA preparation and RNA extraction, and the second is a closed laboratory of 300 square feet used for printing and scanning of slides. The available equipment includes a liquid handler (Qiagen) and Tetrad thermocycler to provide for front-end procedures (preparing cDNAs), a Biorobotics printer, and an Axon Scanner. The services of the array core include; Provision of 2000-gene mouse and human glass array slides, practice slides, and custom arrays. Full slide processing service including hybridization, scanning and quantitation. This will include RNA extraction, labeling, hybridization, scanning and analysis.